Small transport in cruise encounters formation of migrant birds and takes evasive action.

Attributes
ACN	126493
Time
Date	198910
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : agc
State Reference	PA
Altitude	msl bound lower : 2600 msl bound upper : 3000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : pit
Operator	common carrier : air taxi
Make Model Name	Small Transport, Low Wing, 2 Recip Eng
Flight Phase	cruise other
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : cfi pilot : commercial pilot : instrument
Experience	controller military : 4 controller non radar : 2 controller radar : 2 flight time last 90 days : 80 flight time total : 1700 flight time type : 350
ASRS Report	126493
Person 2
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Events
Anomaly	altitude deviation : excursion from assigned altitude inflight encounter other
Independent Detector	other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	other

Narrative:

Level 3000' in VFR flight conditions on IFR flight plan on vectors from pittsburgh approach control. Spotted approximately 20-25 geese in a 'V' formation at my 1 O'clock and 1-2 NM, moving from my right to left, at same altitude. At first, I expected the formation would dive as in past experience. Although only the 1ST row did (dive). Therefore, only 2 courses of action would be possible to avoid almost certain bird impact. I chose to dive to the right (birds were moving right to left). No impact was made although a loss of 350-400' was made to prevent impact. Immediate return to altitude was made. Approach control made no remarks to my evasive actions. Future prevention: none known.

Original NASA ASRS Text

Title: SMT IN CRUISE ENCOUNTERS FORMATION OF MIGRANT BIRDS AND TAKES EVASIVE ACTION.

Narrative: LEVEL 3000' IN VFR FLT CONDITIONS ON IFR FLT PLAN ON VECTORS FROM PITTSBURGH APCH CTL. SPOTTED APPROX 20-25 GEESE IN A 'V' FORMATION AT MY 1 O'CLOCK AND 1-2 NM, MOVING FROM MY RIGHT TO LEFT, AT SAME ALT. AT FIRST, I EXPECTED THE FORMATION WOULD DIVE AS IN PAST EXPERIENCE. ALTHOUGH ONLY THE 1ST ROW DID (DIVE). THEREFORE, ONLY 2 COURSES OF ACTION WOULD BE POSSIBLE TO AVOID ALMOST CERTAIN BIRD IMPACT. I CHOSE TO DIVE TO THE RIGHT (BIRDS WERE MOVING RIGHT TO LEFT). NO IMPACT WAS MADE ALTHOUGH A LOSS OF 350-400' WAS MADE TO PREVENT IMPACT. IMMEDIATE RETURN TO ALT WAS MADE. APCH CTL MADE NO REMARKS TO MY EVASIVE ACTIONS. FUTURE PREVENTION: NONE KNOWN.

Data retrieved from NASA's ASRS site as of August 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.